syscall.c

/*------------------------------------------------------------------------*/
/* Sample code of OS dependent controls for FatFs                         */
/* (C)ChaN, 2014                                                          */
/*------------------------------------------------------------------------*/


#include <stdlib.h>
#include "../ff.h"


#if _FS_REENTRANT
/*------------------------------------------------------------------------*/
/* Create a Synchronization Object                                        */
/*------------------------------------------------------------------------*/
/* This function is called in f_mount() function to create a new
/  synchronization object, such as semaphore and mutex. When a 0 is returned,
/  the f_mount() function fails with FR_INT_ERR.
*/

int ff_cre_syncobj (    /* 1:Function succeeded, 0:Could not create the sync object */
        BYTE vol,                       /* Corresponding volume (logical drive number) */
        _SYNC_t *sobj           /* Pointer to return the created sync object */
)
{
        int ret;


        *sobj = CreateMutex(NULL, FALSE, NULL);         /* Win32 */
        ret = (int)(*sobj != INVALID_HANDLE_VALUE);

//      *sobj = SyncObjects[vol];                       /* uITRON (give a static sync object) */
//      ret = 1;                                                        /* The initial value of the semaphore must be 1. */

//      *sobj = OSMutexCreate(0, &err);         /* uC/OS-II */
//      ret = (int)(err == OS_NO_ERR);

//      *sobj = xSemaphoreCreateMutex();        /* FreeRTOS */
//      ret = (int)(*sobj != NULL);

        return ret;
}



/*------------------------------------------------------------------------*/
/* Delete a Synchronization Object                                        */
/*------------------------------------------------------------------------*/
/* This function is called in f_mount() function to delete a synchronization
/  object that created with ff_cre_syncobj() function. When a 0 is returned,
/  the f_mount() function fails with FR_INT_ERR.
*/

int ff_del_syncobj (    /* 1:Function succeeded, 0:Could not delete due to any error */
        _SYNC_t sobj            /* Sync object tied to the logical drive to be deleted */
)
{
        int ret;


        ret = CloseHandle(sobj);        /* Win32 */

//      ret = 1;                                        /* uITRON (nothing to do) */

//      OSMutexDel(sobj, OS_DEL_ALWAYS, &err);  /* uC/OS-II */
//      ret = (int)(err == OS_NO_ERR);

//  vSemaphoreDelete(sobj);             /* FreeRTOS */
//      ret = 1;

        return ret;
}



/*------------------------------------------------------------------------*/
/* Request Grant to Access the Volume                                     */
/*------------------------------------------------------------------------*/
/* This function is called on entering file functions to lock the volume.
/  When a 0 is returned, the file function fails with FR_TIMEOUT.
*/

int ff_req_grant (      /* 1:Got a grant to access the volume, 0:Could not get a grant */
        _SYNC_t sobj    /* Sync object to wait */
)
{
        int ret;

        ret = (int)(WaitForSingleObject(sobj, _FS_TIMEOUT) == WAIT_OBJECT_0);   /* Win32 */

//      ret = (int)(wai_sem(sobj) == E_OK);                     /* uITRON */

//      OSMutexPend(sobj, _FS_TIMEOUT, &err));          /* uC/OS-II */
//      ret = (int)(err == OS_NO_ERR);

//      ret = (int)(xSemaphoreTake(sobj, _FS_TIMEOUT) == pdTRUE);       /* FreeRTOS */

        return ret;
}



/*------------------------------------------------------------------------*/
/* Release Grant to Access the Volume                                     */
/*------------------------------------------------------------------------*/
/* This function is called on leaving file functions to unlock the volume.
*/

void ff_rel_grant (
        _SYNC_t sobj    /* Sync object to be signaled */
)
{
        ReleaseMutex(sobj);             /* Win32 */

//      sig_sem(sobj);                  /* uITRON */

//      OSMutexPost(sobj);              /* uC/OS-II */

//      xSemaphoreGive(sobj);   /* FreeRTOS */
}

#endif




#if _USE_LFN == 3       /* LFN with a working buffer on the heap */
/*------------------------------------------------------------------------*/
/* Allocate a memory block                                                */
/*------------------------------------------------------------------------*/
/* If a NULL is returned, the file function fails with FR_NOT_ENOUGH_CORE.
*/

void* ff_memalloc (     /* Returns pointer to the allocated memory block */
        UINT msize              /* Number of bytes to allocate */
)
{
        return malloc(msize);   /* Allocate a new memory block with POSIX API */
}


/*------------------------------------------------------------------------*/
/* Free a memory block                                                    */
/*------------------------------------------------------------------------*/

void ff_memfree (
        void* mblock    /* Pointer to the memory block to free */
)
{
        free(mblock);   /* Discard the memory block with POSIX API */
}

#endif